JP2001013677A - Method of washing pellicle housing container - Google Patents

Abstract

PROBLEM TO BE SOLVED: To eliminate the need for the manpower of washing work and to improve the washing capacity and productivity by successively executing a shower washing to spray a washing liquid and an ultrasonic washing with a surfactant and in pure water, then executing dehydration and drying. SOLUTION: This method consists of respective stages for the shower washing to spray the washing liquid from a nozzle, the ultrasonic washing using the surfactant aqueous solution as the washing liquid, the shower washing to spray the pure water from the nozzle, the ultrasonic washing to use the pure water as the washing liquid, dehydrating and drying. The high washing capability may be obtained by executing the ultrasonic washing by taking the arrangement of the wash in shower washing and washing tanks and the flow of the washing liquid into consideration. The washing device is successively arrayed with the shower washing device 121, the ultrasonic washing device 122 using the aqueous surfactant solution, the shower washing device 123 using the pure water, ultrasonic washing device 124 using the pure water, the shower washing device 123 using the pure water, the dehydrating device 125 and the drying device 126 on a washing device stand 120.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an lithography pellicle, and more particularly, to an exposure method using light of substantially 500 nm or less as dust avoidance when manufacturing a semiconductor device such as an LSI or a super LSI or a liquid crystal display panel. The present invention relates to a method for cleaning a container for storing a pellicle for lithography, which is useful for antistatic purposes.

[0002]

2. Description of the Related Art In the manufacture of semiconductors such as LSIs and VLSIs or liquid crystal display panels, patterning is performed by irradiating a semiconductor wafer or a liquid crystal original plate with light.
If dust is attached to the exposure original plate used at this time, the dust absorbs or bends the light, so that the transferred pattern is deformed or the edges are rough, and the base is There is a problem in that the surface is blackened and the dimensions, quality, appearance and the like are impaired. For this reason, these operations are usually performed in a clean room.However, it is difficult to keep the original exposure plate clean even in this clean room. For this purpose, a method of sticking to the surface of an original exposure plate has been adopted. In this case, the foreign matter does not adhere to the surface of the original exposure plate, but adheres to the pellicle film. Therefore, if the focus is adjusted to the pattern surface of the original exposure plate during lithography, the foreign matter on the pellicle film becomes irrelevant to the transfer.

A pellicle is usually prepared by coating a transparent pellicle film made of nitrocellulose, cellulose acetate, etc., which transmits light well, and a good solvent of the pellicle film on the upper end surface of a pellicle frame made of aluminum, stainless steel, polyethylene or the like. And bonded (US Pat. No. 4,861,402).
Further, on the lower end surface of the pellicle frame, an adhesive layer made of a polybutene resin, a polyvinyl acetate resin, an acrylic resin, or the like for mounting on an exposure original plate, and an adhesive layer A release layer (separator) is formed for the purpose of protection. This pellicle has a pellicle film attached to an exposure original plate, and a part of the pellicle frame has an air pressure in order to eliminate the pressure difference between the space on the exposure original plate surrounded by the inside of the pellicle frame and the outside. In order to prevent the intrusion of foreign matter from the air moving through the small holes, a device such as a filter has been devised (Japanese Utility Model Publication No. 63-63).
393703).

To attach a pellicle film to an original exposure plate,
Generally, the pellicle is automatically or manually removed from the container, and immediately inspected for foreign matter on the pellicle film surface and the inner wall of the pellicle frame.The separator is removed. A method of applying a fixed load for a fixed time with a constant load is employed. At this time, in the inspection of foreign matter before bonding, if there is foreign matter of an unacceptable size on the pellicle film surface or the inner wall of the pellicle frame, it can be removed only by a simple method such as air blow based on the material and structure of the pellicle. I can't take it. For this reason, when foreign matter adheres to the pellicle, most of the foreign matter is immediately regarded as defective. For these reasons, during storage and transport, there should be no attachment of foreign matter to the pellicle, and very high cleanliness is required for the pellicle storage container, especially the inner surface thereof.

FIGS. 1A and 1B show a general pellicle container to which the present invention is applied. FIG. 1A is a perspective view, and FIG.
2 is a vertical sectional view taken along line AA of the pellicle storage container shown in FIG. The pellicle container includes an upper lid 1, a tray 2, and a clip 3 for connecting and holding these at four corners. The tray 2 holds and holds a pellicle (not shown), and the upper lid 1 is fitted to the tray 2 to cover the pellicle, thereby preventing damage to the pellicle and adhesion of foreign matter.

[0006] These components are made of aluminum alloy,
Although it is possible to manufacture with metal such as stainless steel,
Generally suitable for mass production, low production cost,
It is manufactured by injection molding a resin because of its smooth surface. As a material of the resin used at this time, for example, ABS, PVC, PP and the like can be mentioned.
Injection molding machines use a hydraulic pressure to feed resin into the mold at high speed,
Since the equipment is used to obtain products by filling at high pressure, the manufacturing site of an injection molding plant generally contains foreign substances such as lubricating oil for machines, grease and other grease, and fiber waste from workers' clothing, etc. It is an unclean environment with a large amount inside. Further, at the time of molding, a release agent (powder or liquid) is also used to prevent the resin from sticking to the mold.
For this reason, the surface of the pellicle storage container delivered from the processor is in an extremely unclean state in which various kinds of foreign substances are attached innumerably.

[0007]

At present, as a low-cost and high-performance cleaning method, ultrasonic cleaning is widely used not only in the semiconductor industry but also in general. Typical features of ultrasonic cleaning include strong cleaning power and the ability to clean every corner even with complex shapes and small ones.
This is due to the basic properties of ultrasonic waves.Even if there is a complex shape or irregularities on the surface, the ultrasonic waves diffract in the cleaning liquid and wrap around to every corner. This is due to the phenomenon that an object reflects ultrasonic waves and transmits the ultrasonic waves to another surface. However, when the material to be cleaned has a low hardness, for example, resin or rubber, a phenomenon occurs in which the irradiated ultrasonic wave is absorbed, and the original cleaning effect cannot be expected. In particular, in a portion not facing the irradiation direction of the ultrasonic wave, the phenomenon that the ultrasonic wave reflected from the irradiated surface reaches cannot be expected at all, and the cleaning ability is significantly reduced. For this reason, it has been impossible to obtain good cleaning quality over the entire surface of the pellicle container only by ultrasonic cleaning for a general resin-made pellicle container having a complicated shape.

For the above-mentioned reason, conventionally, the upper lid 1 and the tray 2
As for the method, a method has been adopted in which, after removing most of the foreign substances by performing a strong scrub cleaning, ultrasonic cleaning is performed in an aqueous solution of a surfactant and then ultrasonic cleaning in pure water. Since the pellicle storage container has many curved surfaces and projections, it is extremely difficult to implement a scrub operation as a device, and therefore, scrub cleaning has been performed manually. Since this method relies on a large amount of cleaning power for manual scrubbing, the cleaning quality varies due to unevenness in manual work, and the physical burden on the worker is extremely large, which is not suitable for mass production. Was.

Further, the washed pellicle storage container must be dried before use, but a general resin pellicle storage container is easily deformed by heat.
There are restrictions on the temperature conditions for forced drying. Depending on the material,
For example, in the case of ABS resin, when heated to 70 ° C. or more, deformation of an unacceptable size as a pellicle storage container occurs. Further, in the case of resin, water does not spread on the surface because of poor wettability to water, and aggregates by surface tension to form droplets. For this reason, drying of the pellicle storage container after washing is extremely difficult due to the low allowable drying temperature and the small surface area of the attached water. Although it depends on the material of the pellicle storage container, when a hot air dryer that blows hot air through a filter is used, it takes about 30 minutes or more to completely dry, and the productivity is extremely poor. For this reason, when processing in large quantities, it was necessary to prepare a remarkably large warm air dryer. However, in practice, the size of a dryer that can be manufactured is limited, and a method of naturally drying by a downflow in a clean room has been adopted. In the case of natural drying, a drying time of 4 hours or more is required, and the productivity is extremely poor. As described above, the conventional drying method has many problems, and the productivity is extremely low.

[0010] On the other hand, the clip 3 is extremely difficult to scrub manually due to its shape.
After several tens to several hundreds were stored in a basket-type cleaning jig and subjected to ultrasonic cleaning in a surfactant aqueous solution, they were rinsed with pure water and dried by natural drying. However, since the material of the clip is also a resin, a great cleaning effect cannot be expected only by ultrasonic cleaning. On the other hand, the clip 3 is an auxiliary component attached to the outside of the pellicle storage container, and is manually removed by an operator when removing the pellicle from the pellicle storage container. For this reason, the cleanliness is not required as high as the top lid or the tray, and although there is a problem pointed out in the above-mentioned cleaning method, the cleanliness sufficiently satisfies the requirement, and the cleaning ability for the clip 3 has been a problem so far. I never did. However, when the method of cleaning the clip is different from that of the upper lid and the tray, it is necessary to prepare another cleaning device for the clip, and there is a problem in productivity. In addition, when the clip is washed in the same process as the upper lid and the tray, since the clip has a complicated shape and a large surface area, and is washed in units of several hundred pieces, after washing in a surfactant aqueous solution, When rinsing with pure water, a large amount of the surfactant is brought into the pure water cleaning tank, which significantly contaminates the cleaning liquid. For this reason, there is a problem in cleaning the clip in the same process as the upper lid and the tray.

Accordingly, an object of the present invention is to provide a method for cleaning a pellicle container which is excellent in cleaning performance and productivity without requiring any manpower for the cleaning operation.

[0012]

The method of cleaning a pellicle container according to the present invention comprises shower cleaning in which a cleaning liquid is sprayed from a nozzle, ultrasonic cleaning in a surfactant aqueous solution, and ultrasonic cleaning in pure water. After performing, dehydration and drying are performed. At this time, between the ultrasonic cleaning in the surfactant aqueous solution and the ultrasonic cleaning in the pure water and / or the ultrasonic cleaning and the dehydration in the pure water, the shower cleaning in which the pure water is blown from the nozzle. Is preferably performed.

Further, in cleaning the pellicle storage container,
During the ultrasonic cleaning in pure water, the cleaning jig is swung together with the cleaning jig once every 0.5 to 5 minutes until the pellicle storage container housed in the cleaning jig completely comes out of the liquid. It is better to let. At the time of ultrasonic cleaning, an ultrasonic wave in which at least two frequencies within a range of 20 to 50 kHz are mixed at the same time, or modulation is continuously performed at a bandwidth of at least 3 kHz or more within a frequency range of 20 to 50 kHz. By using repeated ultrasonic waves, cleaning can be performed more reliably. In the dehydration, a pellicle storage container completely immersed in pure water is placed such that the pellicle mounting surface is vertical and the upper edge of the pellicle storage container is 2-1 to the liquid level.
In a state where the liquid is inclined at an angle within a range of 5 °, the liquid is set at 0.
This is done by pulling up at a pulling speed in the range of 5-20 mm / sec. The washed pellicle storage container is dried by blowing air having a temperature of 50 to 70 ° C. through a ULPA filter at a flow rate of 0.5 m / sec or more. It is desirable to perform a series of processes from washing to drying continuously, and at that time, the pellicle container is automatically transported.

According to the present invention, a jig for cleaning a pellicle storage container may be configured such that an upper lid and a tray, which are components of the pellicle storage container, are separately set so that the pellicle mounting surface is vertical and the pellicle mounting surface is perpendicular to the pellicle mounting surface. Characterized in that it is held by holding portions provided at 2 to 6 places at intervals of 20 to 100 mm in the direction of 、, and particularly, this holding portion is in contact with an upper lid and a tray which are components of the pellicle storage container. It is preferable to have a groove for draining liquid.

The present invention is directed to shower cleaning in which a cleaning liquid is sprayed from a nozzle, ultrasonic cleaning using a surfactant aqueous solution as a cleaning liquid, shower cleaning in which pure water is sprayed from a nozzle, ultrasonic cleaning using pure water as a cleaning liquid, dehydration, and the like. The method includes a method for cleaning the pellicle storage container including the respective drying steps, and a cleaning jig used in the cleaning method. The material, shape, and the like of the pellicle storage container to be used in this cleaning method are not particularly limited, but those formed by injection molding of a resin are particularly effective.

The scrub cleaning by hand is an effective cleaning method for an object to be cleaned which is heavily stained.
It is necessary to adopt a cleaning method with higher cleaning ability. As a result of various studies, it has been found that a high cleaning ability can be obtained by performing ultrasonic cleaning in consideration of the arrangement of the object to be cleaned in the shower cleaning and cleaning tank and the flow of the cleaning liquid. Specifically, the top lid and tray are combined and washed at the same time, and for the clips,
Separately, several tens to several hundreds are washed only with clips. This is because if the clip is washed at the same time as the upper lid and the tray, the ultrasonic wave is absorbed and reflected in the ultrasonic cleaning tank, and there is a concern that the washing may be hindered.

[0017]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, an example of a method for cleaning a pellicle container according to the present invention will be described with reference to the drawings. FIG.
1A is a schematic front view, and FIGS. 2B and 2C are a schematic side view and a schematic plan view, respectively, of a main part of a device for shower cleaning (hereinafter, referred to as a shower cleaning device). FIG.
An apparatus for ultrasonic cleaning in a surfactant aqueous solution (hereinafter referred to as an ultrasonic cleaning apparatus), (a) is a schematic front view,
(B) and (c) are a schematic side view and a schematic plan view of a main part, respectively. 4A and 4B show a case where pure water is used as a cleaning liquid in the shower cleaning apparatus shown in FIG. 2. Similarly, FIG. 4A is a schematic front view, and FIGS. is there. FIGS. 5A and 5B show a case where pure water is used as a cleaning liquid in the ultrasonic cleaning apparatus of FIG. 3, wherein FIG. 5A is a schematic front view, and FIGS. . FIG. 6 is a schematic front view of an apparatus for dehydrating (hereinafter, referred to as a dehydrating apparatus). FIG. 7 is a schematic front view of an apparatus for drying (hereinafter, referred to as a drying apparatus). Each of the schematic front view, schematic side view, and schematic plan view shows a cross-sectional view at a location suitable for description.

Using the shower cleaning apparatus shown in FIG. 2, the upper lid 10 and the tray 11 of the pellicle storage container (hereinafter referred to as the pellicle storage containers 10 and 11 when both the upper lid and the tray are represented) are individually stored in the cleaning jig 12. And charged into the cleaning tank 20. The cleaning liquid 21 is applied to the upper lid 10 and the tray 11 by the nozzle 2.
The dust is sprayed from step 2 to remove dust that is lightly attached to the surface and foreign substances of a type that cannot be removed by ultrasonic cleaning. The cleaning liquid 21 used here is not particularly limited, and tap water, pure water, an aqueous solution of a surfactant, or the like can be used. However, in order to use a large amount of the cleaning liquid, it is desirable to connect a pump 25 to a pipe 27 connected to the cleaning tank 20, and to pass the cleaning liquid through the heater 24 and the filter 23 to circulate and reuse the cleaning liquid as indicated by the arrow. When an aqueous solution of a surfactant is used as the cleaning solution, an antifoaming agent may be added to suppress the generation of a large amount of foam.

The arrangement and the number of the nozzles 22 in the shower cleaning may be appropriately selected so as to cover the entire surfaces of the pellicle storage containers 10 and 11 and to avoid waste, and are not particularly limited. At this time, it is also effective to attach a moving mechanism to the nozzle 22 and move the nozzle 22 during cleaning to spray the cleaning liquid so that the entire surface of the pellicle storage containers 10 and 11 can be cleaned evenly.
Since the purpose of this cleaning device is to remove foreign substances, the higher the flow rate of the cleaning liquid, the higher the cleaning effect can be expected. Therefore, the flow rate of the cleaning liquid is 3 L / min or more per nozzle, and the same applies to the pressure. It is desirable that the pressure be 3 MPa or more.
The washing time is preferably in the range of 1 to 10 minutes. Further, in order to prevent the cleaning liquid 21 from scattering around the cleaning device,
It is preferable to provide a sealing mechanism such as a cover 26 that can be opened and closed.

After the completion of the shower cleaning, ultrasonic cleaning in a surfactant is performed for more precise cleaning. As described above, ultrasonic cleaning is not suitable for general resin pellicle storage containers, but as a result of various studies, by using an ultrasonic cleaning apparatus having a structure as shown in FIG. The above problem was solved, and the cleaning ability was significantly improved.

In the cleaning jig 12, the upper lid 10 and the tray 11 of the pellicle storage container are separately mounted so that they are parallel to each other and the pellicle mounting surface is vertical. Into the washing tank 30 equipped with
The cleaning is performed while the cleaning liquid 31 is supplied into the tank from between the upper lid 10 and the tray 11. Pellicle storage containers 10 and 11 are shown in FIG.
, The ultrasonic vibration plate 32 on the bottom surface
The cleaning liquid 31 is prevented from being absorbed on the way, and the cleaning liquid 31 flows upward without stagnating along the surfaces of the upper lid 10 and the tray 11, so that the ultrasonic waves can be transmitted to the pellicle storage container 10, The foreign matter is peeled off by reaching the entire surface of 11 and the foreign matter peeled off from the surface is immediately carried upward and further carried out of the tank. Due to these synergistic effects, the cleaning power of the cleaning tank 30 for the pellicle storage containers 10 and 11 is greatly improved. At this time, the cleaning liquid 31 during the ultrasonic cleaning is passed through the filter 33 at an exchange rate of 50% / min or more, particularly 80% / min or more with respect to the total amount of the cleaning liquid existing in the cleaning tank 30 while passing through the filter 33. It is desirable to circulate the inside of the pipe 37 by using. If the flow rate is lower than this, the flow of the cleaning liquid as indicated by the arrow in the figure is not formed, and there is a possibility that foreign matter may stay in the tank.

The surfactant to be used must be selected according to the material of the pellicle storage container to be cleaned and the degree of contamination, and the type thereof is not particularly limited. NCW-601A (manufactured by Wako Pure Chemical Industries, trade name)
Is mentioned. If there is no problem in the cleaning ability, it is preferable that the surfactant aqueous solution is neutral in consideration of the burden on the environment and the apparatus. In addition, this concentration may be appropriately determined depending on the type of the surfactant to be used. In the case of Clean Ace S, the concentration is preferably in the range of 3 to 10%. Further, the higher the temperature of the cleaning liquid, the higher the cleaning ability. However, as described above, in the case of a general resin pellicle storage container, deformation due to heat is concerned, so that the temperature is within the range of 25 to 50 ° C. It is good to select according to the material.

The longer the ultrasonic cleaning time in the aqueous surfactant solution, the greater the cleaning ability. Therefore, it is desirable to appropriately select the cleaning time according to the degree of contamination of the pellicle storage container. In the case of the pellicle storage container, there is a concern that the amount of deformation increases with the cleaning time depending on the temperature of the cleaning liquid, and it is desirable to set the range within 3 to 20 minutes from the viewpoint of productivity. If the desired productivity cannot be achieved at this time, the cleaning tank can be divided into a plurality of parts to configure the apparatus, and the tact time per tank can be reduced.

[0024] The higher the sound pressure intensity of the ultrasonic wave, the higher the cleaning ability. However, at a pressure of 100 kPa or more, sometimes the surface of the pellicle storage container is damaged. Further, there is a concern that excessive ultrasonic intensity may accelerate the deterioration of the ultrasonic vibration plate or damage the surface of the cleaning jig. For this reason, in order not to damage the surface of the pellicle storage container and to secure a sufficient cleaning ability, the sound pressure intensity of the ultrasonic wave is set to 25 to 100 k.
It is desirable to be within the range of Pa, particularly 50 kPa.

The frequency of the ultrasonic wave is preferably selected from the range of 20 to 50 kHz. However, if the operation is performed at a single frequency at this time, the sound pressure distribution becomes non-uniform due to the effect of the standing wave. Therefore, it is desirable to prevent the pellicle storage container by swinging it in the tank. Therefore, the frequency is 20 to
It is desirable to employ an ultrasonic cleaner that can generate ultrasonic waves in the range of 50 kHz and at least two frequencies within the range at the same time. The type of such an ultrasonic cleaner is not particularly limited, but one example thereof is a four-frequency mixing type ultrasonic cleaner: Oscillator UO1200FX1-P (trade name, manufactured by Kokusai Denki Eltec). Can be

From the same viewpoint, the frequency is 20 to 50 kHz.
It is also possible to use one that can continuously repeat modulation within the range of z and at least a bandwidth of 3 kHz or more within this range. The type of such an ultrasonic cleaning machine is not particularly limited, but one example thereof is a sweep type ultrasonic cleaning machine: an oscillator UO1200PV-Y.
(Same as above). Furthermore, a cleaning device combining the above two types of cleaning tanks of the ultrasonic oscillation type can also be used. Those that are irradiated with multiple frequencies at the same time have excellent detergency, and the type that performs frequency modulation has the characteristic that the entire detergency can be washed evenly even if the detergency is somewhat weak,
Taking advantage of these differences, each is installed in the most suitable place. For example, an ultrasonic cleaning tank using a surfactant
In the case of using a tank, the cleaning effect can be further enhanced by installing an ultrasonic cleaning tank having a strong detergency in the first tank and an ultrasonic cleaning tank having less unevenness in intensity distribution in the second tank. . The configuration relating to the ultrasonic cleaning tank is not limited to the case where the cleaning liquid is an aqueous solution of a surfactant, but is also effective when pure water or another cleaning liquid is used.

The pellicle containers 10 and 11, which have been subjected to ultrasonic cleaning in the surfactant as described above, are pulled up from the cleaning liquid and sent to the next step. Since the pellicle storage container has a complicated shape and a large surface area, the amount of the attached surfactant is large. For this reason, if it is put into a washing tank using pure water as it is, a large amount of surfactant is mixed into the pure water, so a multi-stage washing tank is required to remove the surfactant,
This leads to an increase in the size of the device and a decrease in productivity. Therefore, after the ultrasonic cleaning in the surfactant aqueous solution, the pellicle storage containers 10 and 11 are charged together with the cleaning jig 12 into the cleaning tank 40 using a shower cleaning device as shown in FIG. It is desirable to perform shower cleaning in which pure water 41 is blown from 42 to completely wash the surfactant from the surfaces of the pellicle storage containers 10 and 11 and the cleaning jig 12.

As a means for supplying pure water, various means can be considered in addition to the illustration, but it is not particularly limited as long as a desired pressure and flow rate can be obtained. However, since the purpose of cleaning here is not to remove foreign substances but to wash away the surfactant attached to the surface, a flow rate is required rather than pressure, and a magnet pump is most suitable for this. I have. Of course, a filter 43 is required on the pump outlet side to remove foreign matter generated from the pump 45. In the shower cleaning device used at this time, the arrangement and the number of the nozzles 42 may be appropriately selected so as to cover the entire surfaces of the pellicle storage containers 10 and 11, and are not particularly limited. During injection, the nozzle 42 is used so that the entire surfaces of the pellicle storage containers 10 and 11 can be washed without unevenness.
It is also effective to use a mechanism that can move the. The injection flow rate of pure water may be sufficient if the amount of surfactant attached to the surfaces of the pellicle storage containers 10 and 11 can be washed away, and it is preferable to inject 0.5 to 2 minutes at 2 to 5 L / min per nozzle. desirable. The pressure is preferably set to 0.05 MPa or more. Further, in order to prevent the liquid from scattering around the apparatus, it is desirable to provide a sealing means such as a cover 46 that can be opened and closed.

After removing the surfactant as described above, ultrasonic cleaning is performed in pure water using an ultrasonic cleaning apparatus shown in FIG. 5 in order to perform more precise rinsing and removal of foreign substances. This cleaning device may basically have the same structure as that using the above-mentioned surfactant aqueous solution, but there is a concern that the purity of pure water is gradually reduced only by circulation, A pipe 57 is connected as shown in FIG. 5 to supply pure water of high purity from a water supply pipe 48, while a liquid overflowing from the upper edge of the cleaning tank 50 is drained to a drain pipe 49.
Drain from In the cleaning, it is necessary to maintain the desired flow rate by circulating the cleaning liquid 51 by the pump 55 and also maintain the purity. The flow rate of the pure water supplied at this time is preferably 10% / min or more of the total volume of the pure water in the cleaning tank 50.

The ultrasonic cleaning in pure water has a problem that does not occur when an aqueous solution of a surfactant is used. In ultrasonic cleaning, cavitation is generated by irradiating ultrasonic waves into the liquid, and cleaning is performed by using a shock wave when the bubbles are destroyed. Due to poor wettability with pure water, if cavitation bubbles are generated on the surface, the bubbles will adhere as they are. In the vicinity of the attached air bubbles, the irradiated ultrasonic waves are obstructed by the air bubbles, which hinders cleaning.
Also, if the air bubbles remain on the surface as they are, they will pop out during the drying and become water droplets, leading to an extension of the drying time.

Therefore, as a result of various studies to solve this, as a result of using a rocking device such as a single-axis robot including the rocking arm 56 and the drive mechanism 59, the ultra-high-pressure water in pure water was used. It has been found that this can be prevented by swinging the cleaning jig 12 up and down together with the pellicle storage containers 10 and 11 completely up to the level where the pellicle storage containers 10 and 11 come out of the liquid during the ultrasonic cleaning. The frequency of the oscillation needs to be determined from the relationship with the cleaning time. However, since the number of attached bubbles continues to increase in proportion to the cleaning time, the frequency of once / 0.5 to 3 minutes is used. It is good to repeat several times during the process. Further, the swing speed at that time is not particularly limited, but the productivity and the cleaning tank 5 are not limited.
Considering the scattering of the liquid around 0, it is desirable that the distance be between 20 and 150 mm / sec. With respect to the swinging operation, it is not necessary to hold the liquid on the liquid surface after being pulled up, and it is preferable to immediately immerse it in pure water. As a method that brings the same effect, a method such as applying a jet to the surface in pure water is also conceivable, but considering the case of simultaneously processing a plurality of pellicle storage containers,
The arrangement of the nozzles for discharging the jet is complicated and difficult. It is also undesirable that an object other than an object to be cleaned such as a nozzle and its piping is installed in the cleaning tank, because it causes unnecessary reflection of ultrasonic waves and generation of foreign matter.

The above-mentioned rocking during the ultrasonic cleaning in pure water can remove bubbles to such an extent that the cleaning is not affected, but lacks certainty. If air bubbles remain, a serious problem occurs during drying as described above. Therefore, it is desirable to remove air bubbles by some method in order to more reliably remove air bubbles. Therefore, as a result of various studies, after ultrasonic cleaning in pure water, shower cleaning in which pure water is sprayed with a nozzle is again performed to completely remove residual air bubbles, and then to perform dehydration. I found something that could be solved. As the device used at this time, the same device as the shower cleaning device shown in FIG. 4 is suitable. It should be noted that the nozzle 42 and the pipe 47 are required to have a high degree of cleanliness because the cleaning stage is close to the finishing stage. By using air in addition to the above pure air,
It is thought that the same effect can be achieved, but air is not desirable because there is a concern that foreign matter may adhere.

The pellicle container, which has been washed as described above, is then transferred to a drying step. If the pellicle container is dried as it is, the allowable drying temperature is low as described above, Due to the small surface area of the existing water, the drying time becomes extremely long. Various methods such as hot air drying, direct heating using an infrared lamp, spin drying, and an air knife can be used as the drying method.However, in the case of a pellicle storage container, extremely high cleanliness is required. If the airflow in the clean room such as knives is significantly disturbed or the operation is severe,
There is a possibility that foreign matter may be newly attached, which is not desirable. In addition, direct heating using an infrared lamp or the like makes it difficult to uniformly heat the entire pellicle container having a complicated shape, and promotes deformation. For this reason, hot air drying is most suitable in consideration of adhesion and deformation of foreign matter.

Various investigations were conducted on the conditions of hot air drying, and it was found that it was impossible to dry the pellicle container in a short time while preventing deformation of the pellicle container within the range of selectable conditions. Therefore, it was studied to perform dehydration before drying the pellicle storage container. Dehydration is generally performed by a method such as air blowing, but as a result of various studies, FIG.
Pellicle storage containers 10 and 11
It was found that a method of completely immersing the entire pellicle mounting surface of the cleaning jig 12 in pure water 61 so that the pellicle mounting surface was vertical, and then slowly pulling it up to dehydrate was effective. Cleaning jig 1
2 is immersed and pulled up by an arm 66 attached to a drive mechanism 69. This method has the advantages that there is no risk of causing foreign matter to adhere without disturbing the airflow in the clean room, the device structure is simple, and batch processing for simultaneously processing a plurality of pellicle storage containers is easy. .

At this time, during the pulling operation, the cleaning jig 12 to which the pellicle containers 10 and 11 are attached is preferably pulled up so that the inclination angle α with respect to the liquid surface 62 is in the range of 2 to 15 °. If the inclination angle α is less than 2 °, the drainage of the outer edges of the pellicle storage containers 10 and 11 becomes extremely poor. Also, the lower the pulling speed from the liquid level at this time, the better, and it is better to be within the range of 0.2 to 20 mm / sec. In order to further increase the productivity, the pulling speed can be changed, and the pulling speed is set to 0.2 to 20 mm.
It is preferable that a portion having a complicated shape, which is difficult to drain, passes slowly through the liquid surface 62 while keeping the speed within a range of / sec.

The temperature of the pure water 61 in the dewatering tank 60 is
It is necessary to select an appropriate one according to the material of the pellicle storage containers 10 and 11 and the clean state of the surface. However, if the temperature is too low, it takes time to raise the temperature in the subsequent drying step, and if the temperature is high, the containers may be deformed. Therefore, the temperature is in the range of 20 to 80 ° C., and especially 20 to 5 for a general resin pellicle container.
Desirably, it is 0 ° C.

The pellicle container subjected to the dehydration treatment after washing as described above can be completely dried by a drying device, more specifically, a hot air dryer. The drying device has, for example, a structure as shown in FIG. 7. Hot air is supplied into the device through an HEPA filter 77 by an outside air introduction fan 76, heated by a heater 74, passed through an ULPA filter 73, and the pellicle storage container 10. It flows toward 11. At this time, the hot air is ULPA or HEPA
It is necessary to remove dust to a high level using high-performance filters 73 and 77 such as those described above. The flow of the hot air is not particularly limited, but in consideration of the connection with the transfer device, the flow of the hot air is preferably from the top to the bottom as shown by an arrow (reference numeral 78) in FIG. The temperature of the hot air is controlled by the pellicle storage containers 10 and 11.
Although it depends on the material, the temperature is preferably in the range of 50 to 80 ° C., particularly in the range of 55 to 70 ° C. for the resin-made pellicle container, and drying is preferably performed in 5 to 15 minutes. The flow rate of hot air is
The effect on the drying time is not very large, but is almost 0.
It is desirable to set it to 5 mm / sec. The dried pellicle storage container depends on its material and drying conditions, but it may take 10 to 10 hours.
A cooling time of at least a minute is required.

Up to this point, the method of cleaning the upper lid and the tray has been described in detail. The method of cleaning the clip, another component of the pellicle storage container, will be described in detail below. It is preferable to wash the clips separately from the upper lid and the tray and collectively in tens to hundreds of clips using only the clips. This is because, as described above, when the clip is cleaned at the same time as the upper lid and the tray, there is a concern that the ultrasonic waves are absorbed and reflected in the ultrasonic cleaning tank, and that the cleaning of the upper lid and the tray is hindered. First, the clips are placed in a basket-type cleaning jig. The volume of the cleaning jig, that is, the number of cleanings performed at one time is not particularly limited, but in order to use the same cleaning device as the top lid and the tray, the cleaning liquid sprayed from the nozzle by the shower cleaning device is used. It is preferable that it fits sufficiently in such an area. After that, it is preferable to perform the cleaning by the same method as the above-described upper lid and tray. The cleaning method of the present invention mainly focuses on cleaning the upper lid and the tray,
Clips can be cleaned cleanly in exactly the same way. Also, drying can be performed completely by the same method.

In the cleaning method described in detail above, what is extremely important is the shape of the cleaning jig. FIGS. 8 and 9 show a cleaning jig used for cleaning the pellicle storage container and the clip, respectively.
Is a schematic front view, (b) is a schematic side view, and (c) is a schematic plan view. FIGS. 10 and 11 are schematic plan views of holding portions for attaching the upper lid 10 and the tray 11 to the cleaning jig, respectively, wherein (a) to (d) show different modes provided in the respective holding portions. The groove is shown.

In order to achieve the ultrasonic cleaning method and the dewatering method of the present invention, the present inventors separately set the upper lid and the tray of the pellicle storage container so that they are parallel to each other, and the pellicle mounting surface is vertical. A cleaning jig was prepared so as to be arranged as follows. As shown in FIG. 8, the cleaning jig includes a base frame 82, a support frame 83 having an upper lid holder 80 and a tray holder 81, and a transport bar 84 for transport.
Consists of The interval 85 between the support frames 83 for supporting the upper lid 10 and the tray 11 is 20 to 10
0 mm, the upper lid holding section 80 and the tray holding section 81
Is preferably 2 to 6 places. The structure and shape of the cleaning jig are not limited to the shape shown in FIG. 8 as long as the cleaning pellicle storage container described above can be held in the above arrangement. In addition, the number of pieces to be attached to one cleaning jig is one set in the example of FIG. 8, but is not limited to this, as long as they are arranged in parallel with the same structure as in FIG. 8. In addition, a plurality of sets of washing can be sufficiently performed.

The shape of the transport bar 84 should be determined based on the balance with the transport device. However, when transporting from above, the transport bar 84 has a structure as shown in FIG. In order to prevent foreign matter from adhering to the support 11, it is preferable to suspend at both ends 86. The transport bar 84 may be omitted when not necessary, such as when the transport bar is lifted from below the base frame 82 and transported by the transport system. As the material of the cleaning jig, an appropriate material may be selected for each component from among those which are unlikely to generate dust during cleaning. In particular, the main structure such as the base frame 82, the support frame 83 of the top lid or tray, and the transport bar 84 may be made of any material as long as it has the necessary strength. For example, Pyrex glass, quartz glass, stainless steel, titanium and Its alloys are mentioned. Further, the upper lid and the tray holding portions 80 and 81 are preferably made of resin in order to prevent the pellicle storage containers 10 and 11 from being damaged. The type of resin does not deteriorate with temperature and chemicals,
Any material that does not easily generate foreign matter when it comes into contact with the pellicle container is not particularly limited, and examples thereof include engineering plastics such as PTFE, PEEK, and POM.

On the other hand, for example, as shown in FIG. 9, the clip cleaning jig includes a clip storage basket 90 for storing clips, an openable lid 91 for preventing clips from flowing out during cleaning,
It comprises a detachable attachment 92. The detachable attachment 92 has a structure that can be attached to and detached from the cleaning jig of the upper lid and the tray shown in FIG. The clip cleaning jig only needs to be able to accommodate a plurality of clips so as not to flow out, and the structure and position of the openable / closable lid 91 and the detachable attachment 92 are not particularly limited thereto. It is of course possible to produce a cleaning jig dedicated to clips with the same structure as in FIG. 8, but from the viewpoint of cost reduction, it is desirable to use a cleaning jig for the top lid and tray as illustrated in FIG. , It is preferable to have a removable structure.

Although the volume of the clip storage basket 90 is not particularly limited, it is desirable to use the same cleaning device as the upper lid and the tray, so that the cleaning liquid sprayed from the nozzle in the above-described shower cleaning device is sufficient. Such a size is preferable. The reinforcing member 93 of the clip storage basket 90 may be a round bar having a diameter of 0.5 to 3 mm because it is feared that the reinforcing member 93 may interfere with ultrasonic waves in ultrasonic cleaning and reduce the cleaning effect. The mesh 94 of the clip storage basket 90 is preferably at least 5 mm or more. Further, the material of these structures is preferably stainless steel from the viewpoint of strength, corrosion resistance and cost.

FIG. 10 shows the details of the portion A in FIG. Top lid 1
The holding portion of the tray 0 and the tray 11 must be designed so that the upper lid 10 or the tray 11 does not fall off when immersed in the cleaning tank and when pulled up. For this purpose,
The upper lid holding portion 100 may have a groove 101 having a cross-sectional shape corresponding to the peripheral portion of the upper lid 10 on its upper surface as shown in FIG. However, the shape of the groove 101 is
Since the gap between the upper lid 10 and the upper lid 10 is small and there is no liquid draining groove, dehydration between the upper lid 10 and the upper lid holding portion 100 becomes insufficient at the time of pulling up and dehydrating, and the drying time is also reduced due to the difficulty of passing hot air at the time of hot air drying. Cause an extension. Therefore, it is desirable that the groove 101 has a shape that does not hinder the dehydration of the cleaning liquid at the time of pulling-up and dehydration.
However, simply widening the fitting portion causes the upper lid 10 to fall off. Therefore, as a result of various studies, FIG.
As shown in (d), it has been found that this problem can be solved by providing a groove for the purpose of draining the liquid further at the contact portion with the upper lid 10 of the groove 101. The shape of this drain groove is
The groove 102 is not limited to the groove 102 having a rectangular cross section as shown in (b), but may be, for example, a groove 103 having an arcuate cross section as shown in (c), a groove 104 having a V-shaped cross section as shown in (d), and the like. Any shape may be used as long as it can fulfill the purpose of draining liquid.

The same can be said for the tray 11. FIG. 11 shows the details of the portion B in FIG. In the shape of the groove 111 of the tray holding unit 110 shown in FIG.
The gap between them is narrow and there is no liquid drain groove.
Dehydration between the tray 11 and the tray holding unit 110 becomes insufficient, and it is difficult for hot air to pass through even during hot air drying, resulting in an increase in drying time. Therefore, it is desirable to provide a groove for drainage as shown in FIGS. 11B to 11D at the contact portion of the groove 111 with the tray 11. The shape of the liquid drain groove is not limited to the groove 112 having a rectangular cross section as shown in (b), but may be, for example, a groove 113 having an arc-shaped cross section as shown in (c), or (d). Any shape, such as a groove 114 having a V-shaped cross section, that can serve the purpose of liquid drainage may be used.

The transport means between the above-mentioned cleaning steps is as follows.
The weight of the pellicle storage container and the cleaning jig is heavy, the process is long, and the operator is extremely tired. In addition, there is a concern that foreign substances may adhere to the pellicle container during transportation. For this reason, it is desirable that the apparatus for performing the cleaning method of the present invention includes an automatic transport mechanism. The cleaning device, the dehydrating device and the drying device used in the above-described cleaning method of the present invention are arranged along the flow of the process, and a transport mechanism is provided in the cleaning device, so that a series of processes can be performed continuously and fully automatically. be able to. FIG.
FIG. 2 is a schematic plan view showing an example of a cleaning apparatus to which the present invention is applied.

The above-described cleaning apparatus is a shower cleaning apparatus 121 on a cleaning apparatus base 120 and an ultrasonic cleaning apparatus 1 using an aqueous solution of a surfactant described in detail with reference to FIGS.
22, a shower cleaning device 123 using pure water, an ultrasonic cleaning device 124 using pure water, a shower cleaning device 123 using pure water, a dehydrating device 125, and a drying device 126 are arranged in this order. The transfer device includes a transfer arm 129, a pulling arm 130, a swing arm 131, a single-axis robot 135 for transfer in a vertical direction (pulling direction), a servomotor 132 for transfer in a horizontal direction, a ball screw 133, and a linear guide 1.
37, stand 127, connecting rod 134 and conveyor 12
8. The pellicle storage containers 10 and 11 are attached to a cleaning jig 12 and processed and transported in the order of processes.

In this example, the swing arm 131 (corresponding to 56 in FIG. 5) of the ultrasonic cleaning apparatus using pure water and the pull-up arm 130 (corresponding to 66 in FIG. 6) of the dehydrator also serve as a transfer arm. After the ultrasonic cleaning with pure water and the pull-up / dehydration process are completed, the device functions as a transfer arm. Each cleaning tank and dehydrating device 12 in each of the cleaning devices 121 to 124
5 is carried out by a single-axis robot 135 disposed for each washing and dewatering device, and the single-axis robot 135 is connected by a connecting rod 134, and is connected to a servomotor. By the operation of 132, all the transfer arms move in conjunction. Drying device 12
The conveyor 128 has been exemplified as the transport means around 6.
Of course, the present invention is not limited to this, and may be a walking beam type or a type in which a robot is arranged before and after the drying device.

As the structure of the transfer device, there are various forms such as a type in which the cleaning tanks are connected by separate and independent transfer devices, in addition to the above-described device in which all the steps are integrated. There is no particular limitation as long as the transport operation can be performed. Various actuators such as a combination of a general-purpose robot, an air cylinder, a servomotor and a ball screw can be used as the actuator. However, in order to prevent foreign matter from adhering to the object to be cleaned, it is desirable that these driving sections are shielded from the surroundings by an appropriate cover, and the inside thereof is always kept at a lower pressure than the surroundings by local exhaust.

As shown in the schematic front view of FIG. 13, the method of supporting the cleaning jig 12 in the transfer device includes (a) a method of suspending from above, and (b) a method of holding from below. However, there is no particular limitation. But,
When holding the cleaning jig 12 from below, the holding arm 13
Since the structure of FIG. 9 becomes complicated,
It is preferable to adopt a method of suspending from above shown in (a).
The transfer device has a structure in which hooks 138 are provided at two locations below the transfer arm 129, and the cleaning jig has a transfer bar 84 at an upper position at a position corresponding to the hook 138. At this time, the fitting portion between the hook 138 and the transport bar 84 can be easily suspended when the hook 138 scoops up the transport bar 84 from below, and the pellicle storage containers 10 and 11 and the cleaning jig 12 are moved during the transport. Shape that does not swing. FIG. 13C shows details of a fitting portion between the hook 138 and the transport bar 84. The hook 138 and the transport bar 84 can be easily suspended, and in order to enhance stability during transport, the mutual fitting portion is tapered, and the angle β is in the range of 30 to 75 °. Good.

[0051]

EXAMPLES The cleaning method of the present invention will be described below with reference to examples and comparative examples. (Example 1) The cleaning method of the present invention was performed using a cleaning apparatus similar to that shown in Fig. 12, which was placed in a "class 10" clean room. First, the upper lid 10 and the tray 11 of the pellicle storage container are attached to the cleaning jig 12 having the structure shown in FIG. 8, and the flow rate is set to 4 L / min per nozzle and the pressure is set to 0. Washing was performed at 3 MPa for 5 minutes. Next, using the ultrasonic cleaning device shown in FIG. 3, a surfactant: Clean Ace S (described above)
Was dissolved in pure water at a concentration of 10% as a cleaning solution,
Ultrasonic cleaning was performed for 5 minutes. At this time, the cleaning liquid was circulated at a flow rate of 40 L / min with respect to a tank volume of 50 L while controlling the temperature at 30 ° C. at a constant value. 4 for ultrasonic cleaner
Frequency mixing type ultrasonic cleaner: Oscillator UO1200FX1-
Ultrasonic waves were applied at a sound pressure intensity of 50 kPa using P (described above). Next, pure water is sprayed using the shower cleaning device shown in FIG.
1 and from the surface of the cleaning jig 12. The flow rate is 2 L / min per nozzle and the pressure is 0.05 MPa.
Was performed for a minute.

After removing the surfactant by this, FIG.
The ultrasonic cleaning was performed in pure water using the ultrasonic cleaning apparatus shown in FIG. Pure water was supplied from the pure water apparatus at a flow rate of 10 L / min while circulating the pure water at a flow rate of 40 L / min with respect to the capacity of the cleaning tank of 50 L. The temperature of the pure water was 30 ° C., and washing was performed for 5 minutes. The same ultrasonic cleaner as described above was used, and ultrasonic waves were irradiated under the condition of a sound pressure intensity of 50 kPa. Further, during cleaning, the pellicle storage containers 10 and 11 are moved together with the cleaning jig 12 at a frequency of once / minute and at a speed of 50 mm / h using a swinging device including a driving mechanism 59 and a swinging arm 56.
Rocked in seconds. Next, pure water was sprayed using the shower cleaning device shown in FIG. 4 to completely remove air bubbles remaining on the surfaces of the pellicle storage containers 10 and 11. Cleaning was performed for 1 minute at a flow rate of 2 L / min per nozzle and a pressure of 0.05 MPa.

After the washing is completed in this manner, the entire pellicle storage containers 10 and 11 are immersed in pure water using a dehydrator shown in FIG. went. At this time, the inclination angle α of the cleaning jig 12 with respect to the water surface is 10 °, and the pulling speed is 1 m.
m / sec. The temperature of the pure water was 35 ° C., and pure water was supplied at a flow rate of 10 L / min from the water supply pipe 48 while circulating at a flow rate of 40 L / min with respect to a volume of 50 L of the dewatering tank 60. Drying was performed for 10 minutes at a flow rate of 1.0 m / sec and a temperature of 70 ° C. using a hot air dryer having a structure shown in FIG. As described above, the inside of the upper lid 10 and the tray 11 of the 50 pellicle storage containers that had been washed and dried were visually inspected in a dark room with a 400,000-lux condenser lamp. as a result,
No foreign matter which could be visually confirmed remained in all 50 pieces.

(Comparative Example 1) Surfactant: A 10% aqueous solution of Clean Ace S (described above) was infiltrated into a non-woven fabric made of polyvinyl alcohol: Velklin (trade name, manufactured by Iuchi Seieido Co., Ltd.) and stored in a pellicle manually. After scrubbing the entire surface of the container top lid 10 and the tray 11 thoroughly and rinsing with pure water, FIG. 14 (a) is a schematic front view, (b) is a schematic side view, and (c) is a schematic plan view. Are contained in the two tanks 142 and 143 of the Pyrex glass cleaning jig 12 shown in FIG. The cleaning jig 12 is put together with the pellicle storage containers 10 and 11 in FIG.
[(A) is a schematic front view, and (b) and (c) are a schematic side view and a schematic plan view, respectively, of a main part]. Using the indicated ultrasonic cleaning apparatus, ultrasonic cleaning was performed with a 10% pure aqueous solution of a surfactant under the same conditions and method as in the above-described example. Thereafter, ultrasonic cleaning was performed in pure water for 10 minutes using the same ultrasonic cleaning device. Except that the cleaning liquid is pure water and that pure water is supplied at a flow rate of 10 L / min from a pure water apparatus (not shown), the specifications of the cleaning apparatus and the cleaning conditions are as follows. Same as case. The pellicle storage containers 10 and 11 having been washed are left on a table having a height of 1300 mm from the floor while being placed in the cleaning jig 12,
It was air-dried for 5 hours while paying careful attention to the surroundings so that foreign matter did not adhere. All the operations in this comparative example were performed in a “class 10” clean room.

After cleaning and drying, the inside of each of the 50 upper lids 10 and trays 11 was visually inspected in a dark room with a 400,000 lux condenser lamp. As a result, no foreign matter that could be visually confirmed remained in all 50 pieces. Further, when the pellicle was stored in the washed pellicle storage container and transported, a confirmation test was performed to determine whether or not foreign matter was attached to the pellicle. Fifty pellicles, each of which was confirmed to have no foreign matter attached, were stored in each of the pellicle storage containers washed in the above-described example and this comparative example. The periphery of each pellicle storage container is covered with a cushioning material, and each of the five pellicle storage containers is packed in the same cardboard box.
It was transported back and forth over a distance of km by truck. After that, the pellicle was taken out of the pellicle storage container in the clean room, and visually inspected using a laser surface inspection device manufactured by Hitachi Electronics Engineering and a focusing lamp of 400,000 lux. Foreign material inspection was performed on the outer wall. As a result, with respect to the pellicle storage container washed in the present comparative example, 0.5 to 1 μm
However, in the pellicle container cleaned in Example 1, no foreign matter was observed in all of the 50 samples.

(Comparative Example 2) Fifty pellicle storage containers were cleaned in the same manner as in the above embodiment, and after ultrasonic cleaning with pure water without performing shower cleaning and dehydration for the purpose of defoaming. Immediately, it was dried with a hot air dryer. As a result, none of 50 samples could be dried in 10 minutes.

(Comparative Example 3) With respect to 50 pellicle storage containers, the upper lid holding portion has the shape shown in FIG. 10A and the tray holding portion has the shape shown in FIG. Using a cleaning jig, a series of processes from cleaning to drying were performed in exactly the same manner as in the above-described example. After drying, cover 10
As a result, water droplets were found to remain in contact with the upper lid holding portion 80 in 24 of 50 samples. In the tray, 38 out of 50 samples
Regarding the individual pieces, water droplets were observed at the contact portions with the tray holding portion 81.

[0058]

According to the present invention, the surface of the pellicle container can be cleaned extremely cleanly. Further, a series of operations from washing to drying of the pellicle storage container can be performed continuously, and extremely high productivity is achieved.

[Brief description of the drawings]

1A and 1B show a general pellicle storage container to which the present invention is applied, wherein FIG. 1A is a perspective view, and FIG. 1B is a longitudinal sectional view taken along line AA of FIG.

FIG. 2 shows an example of a shower cleaning device used in the present invention, wherein (a) is a schematic front view, and (b) and (c) are a schematic side view and a schematic plan view of a main part, respectively.

FIG. 3 shows an example of an ultrasonic cleaning apparatus using a surfactant aqueous solution as a cleaning liquid used in the present invention.
(A) is a schematic front view, (b), (c) is a schematic side view and a schematic plan view of a main part, respectively.

FIG. 4 shows an example of a shower cleaning apparatus using pure water as a cleaning liquid, which is used in the present invention, wherein (a) is a schematic front view, (b) and (c) are schematic side views of main parts, respectively. It is a schematic plan view.

FIG. 5 shows an example of an ultrasonic cleaning apparatus using pure water as a cleaning liquid, which is used in the present invention, wherein (a) is a schematic front view, and (b) and (c) are schematic side views of main parts, respectively. And a schematic plan view.

FIG. 6 is a schematic front view showing an example of a dehydrator used in the present invention.

FIG. 7 is a schematic front view showing an example of a drying device used in the present invention.

8A and 8B show an example of a jig for cleaning a pellicle storage container used in the present invention, wherein FIG. 8A is a schematic front view, FIG. 8B is a schematic side view, and FIG. 8C is a schematic plan view.

FIG. 9 shows an example of a clip cleaning jig used in the present invention, wherein (a) is a schematic front view, (b) is a schematic side view,
(C) is a schematic plan view.

FIGS. 10A and 10B are schematic plan views of a holding portion for attaching an upper lid to a cleaning jig, and FIGS. 10A to 10D show different modes of grooves provided in the holding portion.

FIGS. 11A and 11B are schematic plan views of a holding unit for attaching a tray to a cleaning jig, and FIGS. 11A to 11D show different modes of grooves provided in the holding unit; FIGS.

FIG. 12 is a schematic plan view showing an example of a cleaning device to which the present invention is applied.

FIGS. 13A and 13B are schematic front views of a cleaning jig used in the present invention, wherein FIGS. 13A and 13B are different front views of the cleaning jig in different modes. 3 shows details of a fitting portion of the transport bar.

14A and 14B show a jig for cleaning a pellicle storage container used in Comparative Example 1, wherein FIG. 14A is a schematic front view, FIG. 14B is a schematic side view, and FIG. 14C is a schematic plan view.

FIGS. 15A and 15B show an ultrasonic cleaning apparatus used in Comparative Example 1, in which FIG. 15A is a schematic front view, and FIGS.

[Explanation of symbols]

1: upper lid, 2: tray, 3: clip, 10: upper lid (of pellicle storage container), 11: tray (of pellicle storage container), 12: cleaning jig, 20, 30, 40, 5
0, 150: cleaning tank, 21, 31, 51, 151: cleaning liquid, 22, 42: nozzle, 23, 33, 43, 53,
63, 73, 77, 153: filters, 24, 34,
54, 64, 74, 154: heater, 25, 35, 4
5, 55, 65, 155: pump, 26, 46: cover, 27, 37, 47, 57, 67, 157: piping, 3
2, 152: ultrasonic vibration plate, 41, 61: pure water, 4
8: water supply pipe, 49: drain pipe, 56: swing arm, 5
8, 68: support portion, 59, 69: drive mechanism, 60: dehydration tub, 62: liquid surface, 66: pulling arm, α: inclination angle of cleaning jig from liquid surface, 72: drying cabinet, 75: circulation Fan: 76: outside air introduction fan, 78: arrow 80: upper lid holding unit, 81: tray holding unit, 82: base frame, 83: support frame, 84, 141:
Transport bar, 85: interval, 86: both ends (suspension position during transport), 90: clip storage basket, 91: openable lid,
92: attachment / detachment, 93: reinforcement, 94:
Mesh, 100: upper lid holding portion, 101, 111: groove (without liquid drain groove), 102, 112: liquid drain groove of rectangular cross section, 103, 113: liquid drain groove of arc-shaped cross section, 104,
114: V-shaped cross section drainage groove, 110: tray holding unit, 120: cleaning device stand, 121: shower cleaning device, 122: ultrasonic cleaning device using a surfactant aqueous solution, 123: shower cleaning device using pure water , 124:
Ultrasonic cleaning device using pure water, 125: dehydrating device, 1
26: Drying device, 127: Carrier frame, 128:
Conveyor, 129: Transfer arm, 130: Pull-up arm, 131: Swing arm, 132: Servo motor,
133: ball screw, 134: connecting rod, 135:
Single-axis robot, 136: shutter, 137: linear guide, 138: hook, 139: gripping arm, β:
142,1 Taper angle of the fitting part between hook and transfer bar
43: tank,

 ────────────────────────────────────────────────── ─── Continued from the front page F term (reference)

Claims (13)

[Claims] 1. A pellicle characterized by sequentially performing shower cleaning in which a cleaning liquid is sprayed from a nozzle, ultrasonic cleaning in a surfactant aqueous solution, and ultrasonic cleaning in pure water, followed by dehydration and drying. How to clean the storage container. 2. The cleaning of the pellicle container according to claim 1, wherein between the ultrasonic cleaning in the surfactant aqueous solution and the ultrasonic cleaning in pure water, shower cleaning in which pure water is blown from a nozzle is performed. Method. 3. The method for cleaning a pellicle container according to claim 1, wherein between the ultrasonic cleaning in pure water and the dehydration, shower cleaning in which pure water is blown from a nozzle is performed. 4. The method according to claim 1, wherein the ultrasonic cleaning in pure water is performed for 0.5 to 5 minutes.
The pellicle storage container according to any one of claims 1 to 3, wherein the cleaning jig is swung together with the cleaning jig at a frequency of once per minute until the pellicle storage container housed in the cleaning jig completely comes out of the liquid. Cleaning method. 5. The method for cleaning a pellicle container according to claim 1, wherein at the time of ultrasonic cleaning, ultrasonic waves in which at least two frequencies within a range of 20 to 50 kHz are simultaneously mixed. 6. The frequency of the ultrasonic cleaning is 20 to 50.
The method for cleaning a pellicle container according to any one of claims 1 to 4, wherein an ultrasonic wave whose modulation is continuously repeated at least over a bandwidth of at least 3 kHz within a range of kHz is used. 7. A pellicle storage container completely immersed in pure water for dehydration, wherein the pellicle mounting surface is vertical and the upper edge of the pellicle storage container is within a range of 2 to 15 ° with respect to the liquid level. 2. The method for cleaning a pellicle container according to claim 1, wherein the pellicle container is dewatered upward while being tilted at an angle of. 8. The method for raising the liquid from the liquid level by 0.5 to 20 mm
The method for cleaning a pellicle storage container according to claim 7, wherein the cleaning is performed at a pulling rate in a range of / p. 9. The method for cleaning a pellicle container according to claim 1, wherein air having a temperature of 50 to 70 ° C. is blown at a flow rate of 0.5 m / sec or more through an ULPA filter for drying. 10. The method for cleaning a pellicle storage container according to claim 1, wherein a series of processes from cleaning to drying is performed continuously. 11. The method for cleaning a pellicle container according to claim 10, wherein the pellicle container is automatically conveyed. 12. An upper cover and a tray, which are components of the pellicle storage container, are separately placed with their pellicle mounting surfaces vertical to 20 to 1 in a direction perpendicular to the pellicle mounting surface.
A jig for cleaning a pellicle storage container, wherein the jig is held by holding portions provided at two to six places at intervals of 00 mm. 13. The jig for cleaning a pellicle container according to claim 12, wherein the holding portion has a groove for draining the liquid at a contact portion with the upper lid and the tray, which are components of the pellicle container.